Apparatus for treating exhaust gases from a stack



Nov. 18, 1969 w. R. KEOUGH APPARATUS FOR TREATING EXHAUST GASES FROM A STACK Filed NOV. 13, 1967 INVENTOR.

WILLIAM R. KEOUGH.

BY SETTLE, BATCHELDER 8 OLTMAN.

ATT 'YS.

United States Patent US. Cl. 55-230 2 Claims ABSTRACT OF THE DISCLOSURE A device for removing impurities from exhaust gases. The device includes means for producing a water curtain surrounding the open end of a stack and a fan for forcing the exhaust gases through the jacket to remove impurities therefrom.

BACKGROUND OF THE INVENTION The present invention relates generally to the separatron of materials and more particularly to an improved apparatus for removing impurities from an exhaust gas. With the recent emphasis on elimination of air pollution both at the Federal as Well as the State and local levels, most industrial operations are now required to purify any smoke or other polluted material before it is passed into the atmosphere. While various types of devices have been proposed for eliminating impurities from gases emanating from production plants, these devices have not only been exltremely costly, but have not produced the desired re- Su ts.

SUMMARY OF THE INVENTION The present invention provides a simple and inexpensive apparatus for eliminating impurities from exhaust gases. This is accomplished by producing a water jacket surrounding the open end of a conventional stack and forcing the exhaust gases through the water jacket thereby having the gaseous impurities and solid impurities removed from the exhaust gases and carried away by the flow of water in the water jacket.

The primary object of the present invention is to provide an improved apparatus for removing impurities from exhaust gases.

Another object is to provide an apparatus of reducing impurities from an exhaust gas by passing the exhaust gas through a body of water to thereby have the impurities mixed with the water.

A further object is to provide a simple and inexpensive apparatus for performing the above method.

Other objects of this invention will appear in the following description and appended claims reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

The single figure of the drawing shows a cross sectional view of the upper end of the conventional stack having the apparatus of the present invention supported thereon.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

The single figure of the drawing discloses a stack .10 having the exhaust gas purifying system or device 12 supported thereon. The stack has an opening 14 at the upper end through which exhaust gases are passed and normally enter the atmosphere directly.

' quently 3,478,496 Patented Nov. 18, 1969 The exhaust gas purifying device 12 includes a housing 20 surrounding the open end of the stack 10. The housmg 20 includes a substantially planar upper wall 22 and inclined side wall 24 joined by an arcuate section 25. The lower end of the inclined wall 24 has a downwardly depending skirt 26 which is held in spaced relation with respect to the outer surface 28 of the stack to provide a space 30 between the sidewall of the stack and the skirt portion 26, for a purpose to be described later.

A fan 40 is supported within the opening 3-2 defined by the housing or enclosure 20. The fan has a plurality of fan blades 42 and a central hub portion 44 having an arcuate surface 46, for a purpose to be described later. The fan also includes a drive shaft 50 supported at spaced points by bearings 52 and coupled to a motor 54 by a conventional coupling 56. One bearing 52 is fixedly secured to the upper end of the housing 20 while the second bearing and the motor 54 are supported on conventional beams (not shown) at a point spaced above the housing.

According to the invention, means are provided for producing a water jacket or curtain within the enclosure 20. For this purpose, the drive shaft 50 of the fan 40 is hollow and defines an opening 66 connected by a coupling 60 to a water conduit 62 extending from a water supply or source 64. The lower end of the shaft opening 66 is in open communication with an opening 68 defined between a pair of spaced walls 70 and 72 forming part of the fan 40. In the illustrated embodiment, the spaced walls 70, 72 are interconnected by a plurality of spaced brackets 76. Alternatively, the opening 68 may be replaced by a plurality of conduits radially disposed on the fan unit 40 with each conduit having its inner end in open communication with the shaft opening 66.

The lower end of the housing or enclosure 20 defined by the depending skirt portion 26 has a collection trough for collecting the water. The trough 80 has a water outlet opening 82 and an auger 84, for a purpose to be described later.

Means are provided in the stack for producing a positive fiow of exhaust gases from the opening 14. In the illustrated embodiment, this means is shown as a gas burner disposed in a recess 92 spaced below the upper end of the stack. Thus, assuming the exhaust gases to include a combustible material, the burner 90 will ignite the combustible materials carried by the exhaust gas to thereby increase the gaseous fiow through the open end 14. Alternatively, if the exhaust gases do not include a combustible material, the gas burner 90 may be replaced by an air supplied tube for directing pressurized air towards the open end 14 of the stack 10 thereby inducing flow of the gases from the open end of the stack.

Operation A supply of water is fed from the water source 64 through the opening 66 in the rotating fan 40 to produce a continuous water curtain W within the enclosure 20. The water curtain has a downwardly directed component at the point of contact with the inclined surface 24 and is guided along the inner wall of the inner surface of the inclined wall 24 and the skirt portion 26 to be subsecollected within the trough 80. Thus, the upper portion of the fan including the conduit or opening 68 defined by the spaced walls 70 and 72 may be termed a water pump.

Assuming the exhaust gases to include a combustible material, the burner 90 will ignite the combustible materials and the increase in temperature of the exhaust gases will induce a positive flow of a stream of gases through the open end 14 of the stack. These exhaust gases are redirected outwardly by the rotating fan 40 and are forced through the water curtain or jacket W into the space 32 surrounding the water jacket. Of course,

while the exhaust gases are passing through the water curtain, all of the water wettable or water soluble materials carried as impurities by the exhaust gas are mixed with the water and will be carried by the water curtain downwardly into the trough 80. Similarly, any solids which are carried by the gas will be removed from the exhaust gas and be deposited in the trough 80. The flow of exhaust gases outwardly into the space 32 will produce a positive pressure Within the space 32 thus causing the gases to be forced through the water curtain a second time and eventually be directed into the open space 30 defined between the skirt portion 26 and the outer Wall 28 of the stack 10.

By maintaining the water level L Within the trough 80 slightly below the open end of the enclosure 20, the exhaust gases are again forced to flow through the water curtain W along the space between the open end of the enclosure 20 and the upper level of L of the water within the trough 80. This will result in further filtering of the exhaust gases before they are finally passed into the surrounding atmosphere. All of the solids or particulate materials are of course collected in the trough 80 and may readily be removed therefrom by the auger or conveyor 84.

The continuous flow of water through the enclosure 20, collected within the trough 80 may be passed through the outlet opening and returned directly to the water supply 64 or may be passed to a sump for eliminating any solids which may pass through the outlet opening. Of course, the water in the water supply 64 may be pumped from the sump back to the coupling 60 to produce a closed system.

If desired, the exhaust gases may be further filtered by a magnetic filter 100 located in the space between the outer wall of the trough 80 and the skirt portion 26 of the enclosure 20.

While one exemplary embodiment of the invention has been described in detail, it will be apparent to those skilled in the art that the disclosed embodiment may be modified. Therefore, the foregoing description is to be considered exemplary rather than limiting, and the true scope of the invention is that defined in the following claims.

I claim:

1. Apparatus for removing impurities from exhaust gases flowing from the open upper end of an exhaust stack comprising a cap like housing overlying and surrounding the upper end of said stack in spaced relationship thereto, said housing having an enlarged upper end defining a chamber about said stack and a downwardly and inwardly inclined skirt portion extending downwardly from said upper end to an open lower end located below the upper end of said stack, a trough mounted upon and extending around said stack in spaced relationship below the lower end of said housing, and rotating fan means in said housing above the end of said stack for diverting gas flowing upwardly from said stack outwardly into said chamber, means including a water inlet in said housing above and attached to said rotatitng fan means for producing a water curtain within said housing surrounding said fan means and extending downwardly through said chamber to flow downwardly along the inner surface of said inclined skirt portion and thence from the lower end of said housing into said trough.

'2. Apparatus as defined in claim 1 wherein said fan means comprises a plate mounted for rotation about a vertical axis in spaced overlying relationship to the upper end of said stack, and blade means mounted on lower side of said plate and operable to induce a radially outwardly directed flow of exhaust gases from said stack upon rotation of said plate about said axis, and means for driving said plate in rotation about said axis, said means for producing a water curtain comprising means for flowing water onto the upper surface of said plate to cascade downwardly from the periphery of the plate through the radially outwardly directed flow of gases induced by said fan means.

References Cited UNITED STATES PATENTS 1,818,143 8/1931 Lyons 261-126 2,698,745 1/1955 Boucher -230 2,726,853 12/1955 Schleyer et al. 261-89 2,935,375 5/1960 Boucher 55-257 2,937,013 5/1960 Fisher 261-17 3,239,999 3/1966 Price 261-17 3,322,508 5/ 1967 Ungerleider.

3,317,197 5/ 1967 Lohner'et a1. 261-24 REUBEN FRIEDMAN, Primary Examiner C. N. HART, Assistant Examiner US. Cl. X.R. 261-17, 30, 89 

